Some members of the General Assembly are urging the state to set an enforceable limit for a toxic class of chemicals known as PFAS in public drinking water.
PFAS have been found to increase the risk of cancer and affect human development, fertility and the immune system, according to the CDC. They were long used in consumer products like non-stick pans, as well as firefighting foams used on military bases.
There is currently no enforceable federal standard for the chemicals under the Safe Drinking Water Act, so Delaware lawmakers are asking the state to develop its own.
Leaders of the State Senate Environmental and Natural Resources Committee and House Natural Resources Committee sent a letter dated Aug. 1 to Gov. John Carney asking him to direct the Delaware Department of Natural Resources and Environmental Control (DNREC) and the Department of Health and Social Services (DHSS) to develop Maximum Contaminant Level (MCL) rulemakings for PFAS in public drinking water.
“Often the states take the lead in coming up with these different levels,” said Rep. Debra Heffernan, chair of the House Natural Resources Committee. “Perhaps the federal government would do it, but it hasn’t because under our current federal administration, they’re not really doing that much.”
Heffernan and the other lawmakers received a response Friday from the cabinet secretaries saying DNREC and DHSS are working with the EPA toward securing a national MCL, and are exploring the “pros and cons” of setting a state limit in the meantime.
The letter says the departments are convening a group of stakeholders to begin discussions on regulating PFAS, as well as undertaking targeted environmental sampling, planning an area-wide survey and developing a response plan for PFAS and “other emerging contaminants.”
Delaware Public Media asked the Governor’s Office, DNREC and DHSS for a response to the lawmakers’ request prior to Friday’s letter, but did not receive comment.
Dr. Jerry Kauffman of the University of Delaware’s Water Resources Center supports the push for a state-level MCL for PFAS.
“It requires the water purveyors to test for these substances— because if you don’t test for them you’re not going to find them— and then report the results out to the public,” he said. “Then if the levels exceed the standard … then you’re going to either have to find another source of supply or treat for it.”
Several other states have either set or are developing state-level limits for certain PFAS chemicals in drinking water.
Last year New Jersey set an MCL for the PFAS chemical perfluorononanoic acid (PFNA) of 13 parts per trillion (ppt). The state’s agencies have proposed MCLs of 13 and 14 ppt respectively for perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA).
The EPA’s unenforceable health advisory level set in 2016 for combined PFOS and PFOA is 70 ppt.
Kauffman thinks Delaware should follow New Jersey’s lead on the PFAS MCLs it is proposing. “Unless somebody provides other science or risk-based analysis that says it should be less protective than 14 [ppt], I say it should be 14 [ppt],” he said. “Sounds like the window is between 14 and 70 based on the research that’s been done.”
Heffernan says based on the levels proposed in New Jersey, any MCL in Delaware would probably be lower than the EPA health advisory level. "We would need to look at all the data and decide what would be the appropriate level."
She ties the issue to public health. “If we were to come up with a level, then that would be a better way for us to regulate people being exposed, and make sure that our drinking water supplies were lower than that,” she said.
Kauffman thinks the state will end up setting an MCL for PFAS. “Delaware’s always been a leader on the environment. New Jersey has led [on PFAS], and that’s good news because they’re setting a standard,” he said. “But I’m pretty confident that Delaware will set a standard very, very soon.”
“It’s important to protect our drinking water,” he added. “I know it’s going to be expensive, but it’s worth it.”
PFAS are regulated under the Delaware Hazardous Substance Cleanup Act, which addresses sampling for the chemicals in groundwater and surface water.